// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// Package core implements the Ethereum consensus protocol.
package core
import (
"errors"
"fmt"
"io"
"math/big"
mrand "math/rand"
"runtime"
"sync"
"sync/atomic"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/state"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/core/vm"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"github.com/ethereum/go-ethereum/metrics"
"github.com/ethereum/go-ethereum/pow"
"github.com/ethereum/go-ethereum/rlp"
"github.com/ethereum/go-ethereum/trie"
"github.com/hashicorp/golang-lru"
)
var (
chainlogger = logger.NewLogger("CHAIN")
jsonlogger = logger.NewJsonLogger()
blockInsertTimer = metrics.NewTimer("chain/inserts")
ErrNoGenesis = errors.New("Genesis not found in chain")
)
const (
bodyCacheLimit = 256
blockCacheLimit = 256
maxFutureBlocks = 256
maxTimeFutureBlocks = 30
// must be bumped when consensus algorithm is changed, this forces the upgradedb
// command to be run (forces the blocks to be imported again using the new algorithm)
BlockChainVersion = 3
)
// BlockChain represents the canonical chain given a database with a genesis
// block. The Blockchain manages chain imports, reverts, chain reorganisations.
//
// Importing blocks in to the block chain happens according to the set of rules
// defined by the two stage Validator. Processing of blocks is done using the
// Processor which processes the included transaction. The validation of the state
// is done in the second part of the Validator. Failing results in aborting of
// the import.
//
// The BlockChain also helps in returning blocks from **any** chain included
// in the database as well as blocks that represents the canonical chain. It's
// important to note that GetBlock can return any block and does not need to be
// included in the canonical one where as GetBlockByNumber always represents the
// canonical chain.
type BlockChain struct {
config *ChainConfig // chain & network configuration
hc *HeaderChain
chainDb ethdb.Database
eventMux *event.TypeMux
genesisBlock *types.Block
mu sync.RWMutex // global mutex for locking chain operations
chainmu sync.RWMutex // blockchain insertion lock
procmu sync.RWMutex // block processor lock
checkpoint int // checkpoint counts towards the new checkpoint
currentBlock *types.Block // Current head of the block chain
currentFastBlock *types.Block // Current head of the fast-sync chain (may be above the block chain!)
stateCache *state.StateDB // State database to reuse between imports (contains state cache)
bodyCache *lru.Cache // Cache for the most recent block bodies
bodyRLPCache *lru.Cache // Cache for the most recent block bodies in RLP encoded format
blockCache *lru.Cache // Cache for the most recent entire blocks
futureBlocks *lru.Cache // future blocks are blocks added for later processing
quit chan struct{} // blockchain quit channel
running int32 // running must be called atomically
// procInterrupt must be atomically called
procInterrupt int32 // interrupt signaler for block processing
wg sync.WaitGroup // chain processing wait group for shutting down
pow pow.PoW
processor Processor // block processor interface
validator Validator // block and state validator interface
}
// NewBlockChain returns a fully initialised block chain using information
// available in the database. It initialiser the default Ethereum Validator and
// Processor.
func NewBlockChain(chainDb ethdb.Database, config *ChainConfig, pow pow.PoW, mux *event.TypeMux) (*BlockChain, error) {
bodyCache, _ := lru.New(bodyCacheLimit)
bodyRLPCache, _ := lru.New(bodyCacheLimit)
blockCache, _ := lru.New(blockCacheLimit)
futureBlocks, _ := lru.New(maxFutureBlocks)
bc := &BlockChain{
config: config,
chainDb: chainDb,
eventMux: mux,
quit: make(chan struct{}),
bodyCache: bodyCache,
bodyRLPCache: bodyRLPCache,
blockCache: blockCache,
futureBlocks: futureBlocks,
pow: pow,
}
bc.SetValidator(NewBlockValidator(config, bc, pow))
bc.SetProcessor(NewStateProcessor(config, bc))
gv := func() HeaderValidator { return bc.Validator() }
var err error
bc.hc, err = NewHeaderChain(chainDb, config, gv, bc.getProcInterrupt)
if err != nil {
return nil, err
}
bc.genesisBlock = bc.GetBlockByNumber(0)
if bc.genesisBlock == nil {
return nil, ErrNoGenesis
}
if err := bc.loadLastState(); err != nil {
return nil, err
}
// Check the current state of the block hashes and make sure that we do not have any of the bad blocks in our chain
for hash, _ := range BadHashes {
if header := bc.GetHeaderByHash(hash); header != nil {
glog.V(logger.Error).Infof("Found bad hash, rewinding chain to block #%d [%x…]", header.Number, header.ParentHash[:4])
bc.SetHead(header.Number.Uint64() - 1)
glog.V(logger.Error).Infoln("Chain rewind was successful, resuming normal operation")
}
}
// Take ownership of this particular state
go bc.update()
return bc, nil
}
func (self *BlockChain) getProcInterrupt() bool {
return atomic.LoadInt32(&self.procInterrupt) == 1
}
// loadLastState loads the last known chain state from the database. This method
// assumes that the chain manager mutex is held.
func (self *BlockChain) loadLastState() error {
// Restore the last known head block
head := GetHeadBlockHash(self.chainDb)
if head == (common.Hash{}) {
// Corrupt or empty database, init from scratch
self.Reset()
} else {
if block := self.GetBlockByHash(head); block != nil {
// Block found, set as the current head
self.currentBlock = block
} else {
// Corrupt or empty database, init from scratch
self.Reset()
}
}
// Restore the last known head header
currentHeader := self.currentBlock.Header()
if head := GetHeadHeaderHash(self.chainDb); head != (common.Hash{}) {
if header := self.GetHeaderByHash(head); header != nil {
currentHeader = header
}
}
self.hc.SetCurrentHeader(currentHeader)
// Restore the last known head fast block
self.currentFastBlock = self.currentBlock
if head := GetHeadFastBlockHash(self.chainDb); head != (common.Hash{}) {
if block := self.GetBlockByHash(head); block != nil {
self.currentFastBlock = block
}
}
// Initialize a statedb cache to ensure singleton account bloom filter generation
statedb, err := state.New(self.currentBlock.Root(), self.chainDb)
if err != nil {
return err
}
self.stateCache = statedb
self.stateCache.GetAccount(common.Address{})
// Issue a status log for the user
headerTd := self.GetTd(currentHeader.Hash(), currentHeader.Number.Uint64())
blockTd := self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64())
fastTd := self.GetTd(self.currentFastBlock.Hash(), self.currentFastBlock.NumberU64())
glog.V(logger.Info).Infof("Last header: #%d [%x…] TD=%v", currentHeader.Number, currentHeader.Hash().Bytes()[:4], headerTd)
glog.V(logger.Info).Infof("Last block: #%d [%x…] TD=%v", self.currentBlock.Number(), self.currentBlock.Hash().Bytes()[:4], blockTd)
glog.V(logger.Info).Infof("Fast block: #%d [%x…] TD=%v", self.currentFastBlock.Number(), self.currentFastBlock.Hash().Bytes()[:4], fastTd)
return nil
}
// SetHead rewinds the local chain to a new head. In the case of headers, everything
// above the new head will be deleted and the new one set. In the case of blocks
// though, the head may be further rewound if block bodies are missing (non-archive
// nodes after a fast sync).
func (bc *BlockChain) SetHead(head uint64) {
bc.mu.Lock()
defer bc.mu.Unlock()
delFn := func(hash common.Hash, num uint64) {
DeleteBody(bc.chainDb, hash, num)
}
bc.hc.SetHead(head, delFn)
// Clear out any stale content from the caches
bc.bodyCache.Purge()
bc.bodyRLPCache.Purge()
bc.blockCache.Purge()
bc.futureBlocks.Purge()
// Update all computed fields to the new head
currentHeader := bc.hc.CurrentHeader()
if bc.currentBlock != nil && currentHeader.Number.Uint64() < bc.currentBlock.NumberU64() {
bc.currentBlock = bc.GetBlock(currentHeader.Hash(), currentHeader.Number.Uint64())
}
if bc.currentFastBlock != nil && currentHeader.Number.Uint64() < bc.currentFastBlock.NumberU64() {
bc.currentFastBlock = bc.GetBlock(currentHeader.Hash(), currentHeader.Number.Uint64())
}
if bc.currentBlock == nil {
bc.currentBlock = bc.genesisBlock
}
if bc.currentFastBlock == nil {
bc.currentFastBlock = bc.genesisBlock
}
if err := WriteHeadBlockHash(bc.chainDb, bc.currentBlock.Hash()); err != nil {
glog.Fatalf("failed to reset head block hash: %v", err)
}
if err := WriteHeadFastBlockHash(bc.chainDb, bc.currentFastBlock.Hash()); err != nil {
glog.Fatalf("failed to reset head fast block hash: %v", err)
}
bc.loadLastState()
}
// FastSyncCommitHead sets the current head block to the one defined by the hash
// irrelevant what the chain contents were prior.
func (self *BlockChain) FastSyncCommitHead(hash common.Hash) error {
// Make sure that both the block as well at its state trie exists
block := self.GetBlockByHash(hash)
if block == nil {
return fmt.Errorf("non existent block [%x…]", hash[:4])
}
if _, err := trie.NewSecure(block.Root(), self.chainDb, 0); err != nil {
return err
}
// If all checks out, manually set the head block
self.mu.Lock()
self.currentBlock = block
self.mu.Unlock()
glog.V(logger.Info).Infof("committed block #%d [%x…] as new head", block.Number(), hash[:4])
return nil
}
// GasLimit returns the gas limit of the current HEAD block.
func (self *BlockChain) GasLimit() *big.Int {
self.mu.RLock()
defer self.mu.RUnlock()
return self.currentBlock.GasLimit()
}
// LastBlockHash return the hash of the HEAD block.
func (self *BlockChain) LastBlockHash() common.Hash {
self.mu.RLock()
defer self.mu.RUnlock()
return self.currentBlock.Hash()
}
// CurrentBlock retrieves the current head block of the canonical chain. The
// block is retrieved from the blockchain's internal cache.
func (self *BlockChain) CurrentBlock() *types.Block {
self.mu.RLock()
defer self.mu.RUnlock()
return self.currentBlock
}
// CurrentFastBlock retrieves the current fast-sync head block of the canonical
// chain. The block is retrieved from the blockchain's internal cache.
func (self *BlockChain) CurrentFastBlock() *types.Block {
self.mu.RLock()
defer self.mu.RUnlock()
return self.currentFastBlock
}
// Status returns status information about the current chain such as the HEAD Td,
// the HEAD hash and the hash of the genesis block.
func (self *BlockChain) Status() (td *big.Int, currentBlock common.Hash, genesisBlock common.Hash) {
self.mu.RLock()
defer self.mu.RUnlock()
return self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64()), self.currentBlock.Hash(), self.genesisBlock.Hash()
}
// SetProcessor sets the processor required for making state modifications.
func (self *BlockChain) SetProcessor(processor Processor) {
self.procmu.Lock()
defer self.procmu.Unlock()
self.processor = processor
}
// SetValidator sets the validator which is used to validate incoming blocks.
func (self *BlockChain) SetValidator(validator Validator) {
self.procmu.Lock()
defer self.procmu.Unlock()
self.validator = validator
}
// Validator returns the current validator.
func (self *BlockChain) Validator() Validator {
self.procmu.RLock()
defer self.procmu.RUnlock()
return self.validator
}
// Processor returns the current processor.
func (self *BlockChain) Processor() Processor {
self.procmu.RLock()
defer self.procmu.RUnlock()
return self.processor
}
// AuxValidator returns the auxiliary validator (Proof of work atm)
func (self *BlockChain) AuxValidator() pow.PoW { return self.pow }
// State returns a new mutable state based on the current HEAD block.
func (self *BlockChain) State() (*state.StateDB, error) {
return self.StateAt(self.CurrentBlock().Root())
}
// StateAt returns a new mutable state based on a particular point in time.
func (self *BlockChain) StateAt(root common.Hash) (*state.StateDB, error) {
return self.stateCache.New(root)
}
// Reset purges the entire blockchain, restoring it to its genesis state.
func (bc *BlockChain) Reset() {
bc.ResetWithGenesisBlock(bc.genesisBlock)
}
// ResetWithGenesisBlock purges the entire blockchain, restoring it to the
// specified genesis state.
func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) {
// Dump the entire block chain and purge the caches
bc.SetHead(0)
bc.mu.Lock()
defer bc.mu.Unlock()
// Prepare the genesis block and reinitialise the chain
if err := bc.hc.WriteTd(genesis.Hash(), genesis.NumberU64(), genesis.Difficulty()); err != nil {
glog.Fatalf("failed to write genesis block TD: %v", err)
}
if err := WriteBlock(bc.chainDb, genesis); err != nil {
glog.Fatalf("failed to write genesis block: %v", err)
}
bc.genesisBlock = genesis
bc.insert(bc.genesisBlock)
bc.currentBlock = bc.genesisBlock
bc.hc.SetGenesis(bc.genesisBlock.Header())
bc.hc.SetCurrentHeader(bc.genesisBlock.Header())
bc.currentFastBlock = bc.genesisBlock
}
// Export writes the active chain to the given writer.
func (self *BlockChain) Export(w io.Writer) error {
if err := self.ExportN(w, uint64(0), self.currentBlock.NumberU64()); err != nil {
return err
}
return nil
}
// ExportN writes a subset of the active chain to the given writer.
func (self *BlockChain) ExportN(w io.Writer, first uint64, last uint64) error {
self.mu.RLock()
defer self.mu.RUnlock()
if first > last {
return fmt.Errorf("export failed: first (%d) is greater than last (%d)", first, last)
}
glog.V(logger.Info).Infof("exporting %d blocks...\n", last-first+1)
for nr := first; nr <= last; nr++ {
block := self.GetBlockByNumber(nr)
if block == nil {
return fmt.Errorf("export failed on #%d: not found", nr)
}
if err := block.EncodeRLP(w); err != nil {
return err
}
}
return nil
}
// insert injects a new head block into the current block chain. This method
// assumes that the block is indeed a true head. It will also reset the head
// header and the head fast sync block to this very same block if they are older
// or if they are on a different side chain.
//
// Note, this function assumes that the `mu` mutex is held!
func (bc *BlockChain) insert(block *types.Block) {
// If the block is on a side chain or an unknown one, force other heads onto it too
updateHeads := GetCanonicalHash(bc.chainDb, block.NumberU64()) != block.Hash()
// Add the block to the canonical chain number scheme and mark as the head
if err := WriteCanonicalHash(bc.chainDb, block.Hash(), block.NumberU64()); err != nil {
glog.Fatalf("failed to insert block number: %v", err)
}
if err := WriteHeadBlockHash(bc.chainDb, block.Hash()); err != nil {
glog.Fatalf("failed to insert head block hash: %v", err)
}
bc.currentBlock = block
// If the block is better than out head or is on a different chain, force update heads
if updateHeads {
bc.hc.SetCurrentHeader(block.Header())
if err := WriteHeadFastBlockHash(bc.chainDb, block.Hash()); err != nil {
glog.Fatalf("failed to insert head fast block hash: %v", err)
}
bc.currentFastBlock = block
}
}
// Accessors
func (bc *BlockChain) Genesis() *types.Block {
return bc.genesisBlock
}
// GetBody retrieves a block body (transactions and uncles) from the database by
// hash, caching it if found.
func (self *BlockChain) GetBody(hash common.Hash) *types.Body {
// Short circuit if the body's already in the cache, retrieve otherwise
if cached, ok := self.bodyCache.Get(hash); ok {
body := cached.(*types.Body)
return body
}
body := GetBody(self.chainDb, hash, self.hc.GetBlockNumber(hash))
if body == nil {
return nil
}
// Cache the found body for next time and return
self.bodyCache.Add(hash, body)
return body
}
// GetBodyRLP retrieves a block body in RLP encoding from the database by hash,
// caching it if found.
func (self *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue {
// Short circuit if the body's already in the cache, retrieve otherwise
if cached, ok := self.bodyRLPCache.Get(hash); ok {
return cached.(rlp.RawValue)
}
body := GetBodyRLP(self.chainDb, hash, self.hc.GetBlockNumber(hash))
if len(body) == 0 {
return nil
}
// Cache the found body for next time and return
self.bodyRLPCache.Add(hash, body)
return body
}
// HasBlock checks if a block is fully present in the database or not, caching
// it if present.
func (bc *BlockChain) HasBlock(hash common.Hash) bool {
return bc.GetBlockByHash(hash) != nil
}
// HasBlockAndState checks if a block and associated state trie is fully present
// in the database or not, caching it if present.
func (bc *BlockChain) HasBlockAndState(hash common.Hash) bool {
// Check first that the block itself is known
block := bc.GetBlockByHash(hash)
if block == nil {
return false
}
// Ensure the associated state is also present
_, err := state.New(block.Root(), bc.chainDb)
return err == nil
}
// GetBlock retrieves a block from the database by hash and number,
// caching it if found.
func (self *BlockChain) GetBlock(hash common.Hash, number uint64) *types.Block {
// Short circuit if the block's already in the cache, retrieve otherwise
if block, ok := self.blockCache.Get(hash); ok {
return block.(*types.Block)
}
block := GetBlock(self.chainDb, hash, number)
if block == nil {
return nil
}
// Cache the found block for next time and return
self.blockCache.Add(block.Hash(), block)
return block
}
// GetBlockByHash retrieves a block from the database by hash, caching it if found.
func (self *BlockChain) GetBlockByHash(hash common.Hash) *types.Block {
return self.GetBlock(hash, self.hc.GetBlockNumber(hash))
}
// GetBlockByNumber retrieves a block from the database by number, caching it
// (associated with its hash) if found.
func (self *BlockChain) GetBlockByNumber(number uint64) *types.Block {
hash := GetCanonicalHash(self.chainDb, number)
if hash == (common.Hash{}) {
return nil
}
return self.GetBlock(hash, number)
}
// [deprecated by eth/62]
// GetBlocksFromHash returns the block corresponding to hash and up to n-1 ancestors.
func (self *BlockChain) GetBlocksFromHash(hash common.Hash, n int) (blocks []*types.Block) {
number := self.hc.GetBlockNumber(hash)
for i := 0; i < n; i++ {
block := self.GetBlock(hash, number)
if block == nil {
break
}
blocks = append(blocks, block)
hash = block.ParentHash()
number--
}
return
}
// GetUnclesInChain retrieves all the uncles from a given block backwards until
// a specific distance is reached.
func (self *BlockChain) GetUnclesInChain(block *types.Block, length int) []*types.Header {
uncles := []*types.Header{}
for i := 0; block != nil && i < length; i++ {
uncles = append(uncles, block.Uncles()...)
block = self.GetBlock(block.ParentHash(), block.NumberU64()-1)
}
return uncles
}
// Stop stops the blockchain service. If any imports are currently in progress
// it will abort them using the procInterrupt.
func (bc *BlockChain) Stop() {
if !atomic.CompareAndSwapInt32(&bc.running, 0, 1) {
return
}
close(bc.quit)
atomic.StoreInt32(&bc.procInterrupt, 1)
bc.wg.Wait()
glog.V(logger.Info).Infoln("Chain manager stopped")
}
func (self *BlockChain) procFutureBlocks() {
blocks := make([]*types.Block, 0, self.futureBlocks.Len())
for _, hash := range self.futureBlocks.Keys() {
if block, exist := self.futureBlocks.Get(hash); exist {
blocks = append(blocks, block.(*types.Block))
}
}
if len(blocks) > 0 {
types.BlockBy(types.Number).Sort(blocks)
self.InsertChain(blocks)
}
}
type WriteStatus byte
const (
NonStatTy WriteStatus = iota
CanonStatTy
SplitStatTy
SideStatTy
)
// Rollback is designed to remove a chain of links from the database that aren't
// certain enough to be valid.
func (self *BlockChain) Rollback(chain []common.Hash) {
self.mu.Lock()
defer self.mu.Unlock()
for i := len(chain) - 1; i >= 0; i-- {
hash := chain[i]
currentHeader := self.hc.CurrentHeader()
if currentHeader.Hash() == hash {
self.hc.SetCurrentHeader(self.GetHeader(currentHeader.ParentHash, currentHeader.Number.Uint64()-1))
}
if self.currentFastBlock.Hash() == hash {
self.currentFastBlock = self.GetBlock(self.currentFastBlock.ParentHash(), self.currentFastBlock.NumberU64()-1)
WriteHeadFastBlockHash(self.chainDb, self.currentFastBlock.Hash())
}
if self.currentBlock.Hash() == hash {
self.currentBlock = self.GetBlock(self.currentBlock.ParentHash(), self.currentBlock.NumberU64()-1)
WriteHeadBlockHash(self.chainDb, self.currentBlock.Hash())
}
}
}
// InsertReceiptChain attempts to complete an already existing header chain with
// transaction and receipt data.
func (self *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain []types.Receipts) (int, error) {
self.wg.Add(1)
defer self.wg.Done()
// Collect some import statistics to report on
stats := struct{ processed, ignored int32 }{}
start := time.Now()
// Create the block importing task queue and worker functions
tasks := make(chan int, len(blockChain))
for i := 0; i < len(blockChain) && i < len(receiptChain); i++ {
tasks <- i
}
close(tasks)
errs, failed := make([]error, len(tasks)), int32(0)
process := func(worker int) {
for index := range tasks {
block, receipts := blockChain[index], receiptChain[index]
// Short circuit insertion if shutting down or processing failed
if atomic.LoadInt32(&self.procInterrupt) == 1 {
return
}
if atomic.LoadInt32(&failed) > 0 {
return
}
// Short circuit if the owner header is unknown
if !self.HasHeader(block.Hash()) {
errs[index] = fmt.Errorf("containing header #%d [%x…] unknown", block.Number(), block.Hash().Bytes()[:4])
atomic.AddInt32(&failed, 1)
return
}
// Skip if the entire data is already known
if self.HasBlock(block.Hash()) {
atomic.AddInt32(&stats.ignored, 1)
continue
}
// Compute all the non-consensus fields of the receipts
transactions, logIndex := block.Transactions(), uint(0)
for j := 0; j < len(receipts); j++ {
// The transaction hash can be retrieved from the transaction itself
receipts[j].TxHash = transactions[j].Hash()
// The contract address can be derived from the transaction itself
if MessageCreatesContract(transactions[j]) {
from, _ := transactions[j].From()
receipts[j].ContractAddress = crypto.CreateAddress(from, transactions[j].Nonce())
}
// The used gas can be calculated based on previous receipts
if j == 0 {
receipts[j].GasUsed = new(big.Int).Set(receipts[j].CumulativeGasUsed)
} else {
receipts[j].GasUsed = new(big.Int).Sub(receipts[j].CumulativeGasUsed, receipts[j-1].CumulativeGasUsed)
}
// The derived log fields can simply be set from the block and transaction
for k := 0; k < len(receipts[j].Logs); k++ {
receipts[j].Logs[k].BlockNumber = block.NumberU64()
receipts[j].Logs[k].BlockHash = block.Hash()
receipts[j].Logs[k].TxHash = receipts[j].TxHash
receipts[j].Logs[k].TxIndex = uint(j)
receipts[j].Logs[k].Index = logIndex
logIndex++
}
}
// Write all the data out into the database
if err := WriteBody(self.chainDb, block.Hash(), block.NumberU64(), block.Body()); err != nil {
errs[index] = fmt.Errorf("failed to write block body: %v", err)
atomic.AddInt32(&failed, 1)
glog.Fatal(errs[index])
return
}
if err := WriteBlockReceipts(self.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
errs[index] = fmt.Errorf("failed to write block receipts: %v", err)
atomic.AddInt32(&failed, 1)
glog.Fatal(errs[index])
return
}
if err := WriteMipmapBloom(self.chainDb, block.NumberU64(), receipts); err != nil {
errs[index] = fmt.Errorf("failed to write log blooms: %v", err)
atomic.AddInt32(&failed, 1)
glog.Fatal(errs[index])
return
}
if err := WriteTransactions(self.chainDb, block); err != nil {
errs[index] = fmt.Errorf("failed to write individual transactions: %v", err)
atomic.AddInt32(&failed, 1)
glog.Fatal(errs[index])
return
}
if err := WriteReceipts(self.chainDb, receipts); err != nil {
errs[index] = fmt.Errorf("failed to write individual receipts: %v", err)
atomic.AddInt32(&failed, 1)
glog.Fatal(errs[index])
return
}
atomic.AddInt32(&stats.processed, 1)
}
}
// Start as many worker threads as goroutines allowed
pending := new(sync.WaitGroup)
for i := 0; i < runtime.GOMAXPROCS(0); i++ {
pending.Add(1)
go func(id int) {
defer pending.Done()
process(id)
}(i)
}
pending.Wait()
// If anything failed, report
if failed > 0 {
for i, err := range errs {
if err != nil {
return i, err
}
}
}
if atomic.LoadInt32(&self.procInterrupt) == 1 {
glog.V(logger.Debug).Infoln("premature abort during receipt chain processing")
return 0, nil
}
// Update the head fast sync block if better
self.mu.Lock()
head := blockChain[len(errs)-1]
if self.GetTd(self.currentFastBlock.Hash(), self.currentFastBlock.NumberU64()).Cmp(self.GetTd(head.Hash(), head.NumberU64())) < 0 {
if err := WriteHeadFastBlockHash(self.chainDb, head.Hash()); err != nil {
glog.Fatalf("failed to update head fast block hash: %v", err)
}
self.currentFastBlock = head
}
self.mu.Unlock()
// Report some public statistics so the user has a clue what's going on
first, last := blockChain[0], blockChain[len(blockChain)-1]
glog.V(logger.Info).Infof("imported %d receipt(s) (%d ignored) in %v. #%d [%x… / %x…]", stats.processed, stats.ignored,
time.Since(start), last.Number(), first.Hash().Bytes()[:4], last.Hash().Bytes()[:4])
return 0, nil
}
// WriteBlock writes the block to the chain.
func (self *BlockChain) WriteBlock(block *types.Block) (status WriteStatus, err error) {
self.wg.Add(1)
defer self.wg.Done()
// Calculate the total difficulty of the block
ptd := self.GetTd(block.ParentHash(), block.NumberU64()-1)
if ptd == nil {
return NonStatTy, ParentError(block.ParentHash())
}
// Make sure no inconsistent state is leaked during insertion
self.mu.Lock()
defer self.mu.Unlock()
localTd := self.GetTd(self.currentBlock.Hash(), self.currentBlock.NumberU64())
externTd := new(big.Int).Add(block.Difficulty(), ptd)
// Irrelevant of the canonical status, write the block itself to the database
if err := self.hc.WriteTd(block.Hash(), block.NumberU64(), externTd); err != nil {
glog.Fatalf("failed to write block total difficulty: %v", err)
}
if err := WriteBlock(self.chainDb, block); err != nil {
glog.Fatalf("failed to write block contents: %v", err)
}
// If the total difficulty is higher than our known, add it to the canonical chain
// Second clause in the if statement reduces the vulnerability to selfish mining.
// Please refer to http://www.cs.cornell.edu/~ie53/publications/btcProcFC.pdf
if externTd.Cmp(localTd) > 0 || (externTd.Cmp(localTd) == 0 && mrand.Float64() < 0.5) {
// Reorganise the chain if the parent is not the head block
if block.ParentHash() != self.currentBlock.Hash() {
if err := self.reorg(self.currentBlock, block); err != nil {
return NonStatTy, err
}
}
self.insert(block) // Insert the block as the new head of the chain
status = CanonStatTy
} else {
status = SideStatTy
}
self.futureBlocks.Remove(block.Hash())
return
}
// InsertChain will attempt to insert the given chain in to the canonical chain or, otherwise, create a fork. It an error is returned
// it will return the index number of the failing block as well an error describing what went wrong (for possible errors see core/errors.go).
func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
self.wg.Add(1)
defer self.wg.Done()
self.chainmu.Lock()
defer self.chainmu.Unlock()
// A queued approach to delivering events. This is generally
// faster than direct delivery and requires much less mutex
// acquiring.
var (
stats = insertStats{startTime: time.Now()}
events = make([]interface{}, 0, len(chain))
coalescedLogs vm.Logs
nonceChecked = make([]bool, len(chain))
)
// Start the parallel nonce verifier.
nonceAbort, nonceResults := verifyNoncesFromBlocks(self.pow, chain)
defer close(nonceAbort)
for i, block := range chain {
if atomic.LoadInt32(&self.procInterrupt) == 1 {
glog.V(logger.Debug).Infoln("Premature abort during block chain processing")
break
}
bstart := time.Now()
// Wait for block i's nonce to be verified before processing
// its state transition.
for !nonceChecked[i] {
r := <-nonceResults
nonceChecked[r.index] = true
if !r.valid {
block := chain[r.index]
return r.index, &BlockNonceErr{Hash: block.Hash(), Number: block.Number(), Nonce: block.Nonce()}
}
}
if BadHashes[block.Hash()] {
err := BadHashError(block.Hash())
reportBlock(block, err)
return i, err
}
// Stage 1 validation of the block using the chain's validator
// interface.
err := self.Validator().ValidateBlock(block)
if err != nil {
if IsKnownBlockErr(err) {
stats.ignored++
continue
}
if err == BlockFutureErr {
// Allow up to MaxFuture second in the future blocks. If this limit
// is exceeded the chain is discarded and processed at a later time
// if given.
max := big.NewInt(time.Now().Unix() + maxTimeFutureBlocks)
if block.Time().Cmp(max) == 1 {
return i, fmt.Errorf("%v: BlockFutureErr, %v > %v", BlockFutureErr, block.Time(), max)
}
self.futureBlocks.Add(block.Hash(), block)
stats.queued++
continue
}
if IsParentErr(err) && self.futureBlocks.Contains(block.ParentHash()) {
self.futureBlocks.Add(block.Hash(), block)
stats.queued++
continue
}
reportBlock(block, err)
return i, err
}
// Create a new statedb using the parent block and report an
// error if it fails.
switch {
case i == 0:
err = self.stateCache.Reset(self.GetBlock(block.ParentHash(), block.NumberU64()-1).Root())
default:
err = self.stateCache.Reset(chain[i-1].Root())
}
if err != nil {
reportBlock(block, err)
return i, err
}
// Process block using the parent state as reference point.
receipts, logs, usedGas, err := self.processor.Process(block, self.stateCache, self.config.VmConfig)
if err != nil {
reportBlock(block, err)
return i, err
}
// Validate the state using the default validator
err = self.Validator().ValidateState(block, self.GetBlock(block.ParentHash(), block.NumberU64()-1), self.stateCache, receipts, usedGas)
if err != nil {
reportBlock(block, err)
return i, err
}
// Write state changes to database
_, err = self.stateCache.Commit()
if err != nil {
return i, err
}
// coalesce logs for later processing
coalescedLogs = append(coalescedLogs, logs...)
if err := WriteBlockReceipts(self.chainDb, block.Hash(), block.NumberU64(), receipts); err != nil {
return i, err
}
// write the block to the chain and get the status
status, err := self.WriteBlock(block)
if err != nil {
return i, err
}
switch status {
case CanonStatTy:
if glog.V(logger.Debug) {
glog.Infof("[%v] inserted block #%d (%d TXs %v G %d UNCs) (%x...). Took %v\n", time.Now().UnixNano(), block.Number(), len(block.Transactions()), block.GasUsed(), len(block.Uncles()), block.Hash().Bytes()[0:4], time.Since(bstart))
}
events = append(events, ChainEvent{block, block.Hash(), logs})
// This puts transactions in a extra db for rpc
if err := WriteTransactions(self.chainDb, block); err != nil {
return i, err
}
// store the receipts
if err := WriteReceipts(self.chainDb, receipts); err != nil {
return i, err
}
// Write map map bloom filters
if err := WriteMipmapBloom(self.chainDb, block.NumberU64(), receipts); err != nil {
return i, err
}
case SideStatTy:
if glog.V(logger.Detail) {
glog.Infof("inserted forked block #%d (TD=%v) (%d TXs %d UNCs) (%x...). Took %v\n", block.Number(), block.Difficulty(), len(block.Transactions()), len(block.Uncles()), block.Hash().Bytes()[0:4], time.Since(bstart))
}
events = append(events, ChainSideEvent{block, logs})
case SplitStatTy:
events = append(events, ChainSplitEvent{block, logs})
}
stats.processed++
if glog.V(logger.Info) {
stats.report(chain, i)
}
}
go self.postChainEvents(events, coalescedLogs)
return 0, nil
}
// insertStats tracks and reports on block insertion.
type insertStats struct {
queued, processed, ignored int
lastIndex int
startTime time.Time
}
const (
statsReportLimit = 1024
statsReportTimeLimit = 8 * time.Second
)
// report prints statistics if some number of blocks have been processed
// or more than a few seconds have passed since the last message.
func (st *insertStats) report(chain []*types.Block, index int) {
limit := statsReportLimit
if index == len(chain)-1 {
limit = 0 // Always print a message for the last block.
}
now := time.Now()
duration := now.Sub(st.startTime)
if duration > statsReportTimeLimit || st.queued > limit || st.processed > limit || st.ignored > limit {
start, end := chain[st.lastIndex], chain[index]
txcount := countTransactions(chain[st.lastIndex : index+1])
glog.Infof("imported %d block(s) (%d queued %d ignored) including %d txs in %v. #%v [%x / %x]\n", st.processed, st.queued, st.ignored, txcount, duration, end.Number(), start.Hash().Bytes()[:4], end.Hash().Bytes()[:4])
*st = insertStats{startTime: now, lastIndex: index}
}
}
func countTransactions(chain []*types.Block) (c int) {
for _, b := range chain {
c += len(b.Transactions())
}
return c
}
// reorgs takes two blocks, an old chain and a new chain and will reconstruct the blocks and inserts them
// to be part of the new canonical chain and accumulates potential missing transactions and post an
// event about them
func (self *BlockChain) reorg(oldBlock, newBlock *types.Block) error {
var (
newChain types.Blocks
oldChain types.Blocks
commonBlock *types.Block
oldStart = oldBlock
newStart = newBlock
deletedTxs types.Transactions
deletedLogs vm.Logs
deletedLogsByHash = make(map[common.Hash]vm.Logs)
// collectLogs collects the logs that were generated during the
// processing of the block that corresponds with the given hash.
// These logs are later announced as deleted.
collectLogs = func(h common.Hash) {
// Coalesce logs
receipts := GetBlockReceipts(self.chainDb, h, self.hc.GetBlockNumber(h))
for _, receipt := range receipts {
deletedLogs = append(deletedLogs, receipt.Logs...)
deletedLogsByHash[h] = receipt.Logs
}
}
)
// first reduce whoever is higher bound
if oldBlock.NumberU64() > newBlock.NumberU64() {
// reduce old chain
for ; oldBlock != nil && oldBlock.NumberU64() != newBlock.NumberU64(); oldBlock = self.GetBlock(oldBlock.ParentHash(), oldBlock.NumberU64()-1) {
oldChain = append(oldChain, oldBlock)
deletedTxs = append(deletedTxs, oldBlock.Transactions()...)
collectLogs(oldBlock.Hash())
}
} else {
// reduce new chain and append new chain blocks for inserting later on
for ; newBlock != nil && newBlock.NumberU64() != oldBlock.NumberU64(); newBlock = self.GetBlock(newBlock.ParentHash(), newBlock.NumberU64()-1) {
newChain = append(newChain, newBlock)
}
}
if oldBlock == nil {
return fmt.Errorf("Invalid old chain")
}
if newBlock == nil {
return fmt.Errorf("Invalid new chain")
}
numSplit := newBlock.Number()
for {
if oldBlock.Hash() == newBlock.Hash() {
commonBlock = oldBlock
break
}
oldChain = append(oldChain, oldBlock)
newChain = append(newChain, newBlock)
deletedTxs = append(deletedTxs, oldBlock.Transactions()...)
collectLogs(oldBlock.Hash())
oldBlock, newBlock = self.GetBlock(oldBlock.ParentHash(), oldBlock.NumberU64()-1), self.GetBlock(newBlock.ParentHash(), newBlock.NumberU64()-1)
if oldBlock == nil {
return fmt.Errorf("Invalid old chain")
}
if newBlock == nil {
return fmt.Errorf("Invalid new chain")
}
}
if glog.V(logger.Debug) {
commonHash := commonBlock.Hash()
glog.Infof("Chain split detected @ %x. Reorganising chain from #%v %x to %x", commonHash[:4], numSplit, oldStart.Hash().Bytes()[:4], newStart.Hash().Bytes()[:4])
}
var addedTxs types.Transactions
// insert blocks. Order does not matter. Last block will be written in ImportChain itself which creates the new head properly
for _, block := range newChain {
// insert the block in the canonical way, re-writing history
self.insert(block)
// write canonical receipts and transactions
if err := WriteTransactions(self.chainDb, block); err != nil {
return err
}
receipts := GetBlockReceipts(self.chainDb, block.Hash(), block.NumberU64())
// write receipts
if err := WriteReceipts(self.chainDb, receipts); err != nil {
return err
}
// Write map map bloom filters
if err := WriteMipmapBloom(self.chainDb, block.NumberU64(), receipts); err != nil {
return err
}
addedTxs = append(addedTxs, block.Transactions()...)
}
// calculate the difference between deleted and added transactions
diff := types.TxDifference(deletedTxs, addedTxs)
// When transactions get deleted from the database that means the
// receipts that were created in the fork must also be deleted
for _, tx := range diff {
DeleteReceipt(self.chainDb, tx.Hash())
DeleteTransaction(self.chainDb, tx.Hash())
}
// Must be posted in a goroutine because of the transaction pool trying
// to acquire the chain manager lock
if len(diff) > 0 {
go self.eventMux.Post(RemovedTransactionEvent{diff})
}
if len(deletedLogs) > 0 {
go self.eventMux.Post(RemovedLogsEvent{deletedLogs})
}
if len(oldChain) > 0 {
go func() {
for _, block := range oldChain {
self.eventMux.Post(ChainSideEvent{Block: block, Logs: deletedLogsByHash[block.Hash()]})
}
}()
}
return nil
}
// postChainEvents iterates over the events generated by a chain insertion and
// posts them into the event mux.
func (self *BlockChain) postChainEvents(events []interface{}, logs vm.Logs) {
// post event logs for further processing
self.eventMux.Post(logs)
for _, event := range events {
if event, ok := event.(ChainEvent); ok {
// We need some control over the mining operation. Acquiring locks and waiting for the miner to create new block takes too long
// and in most cases isn't even necessary.
if self.LastBlockHash() == event.Hash {
self.eventMux.Post(ChainHeadEvent{event.Block})
}
}
// Fire the insertion events individually too
self.eventMux.Post(event)
}
}
func (self *BlockChain) update() {
futureTimer := time.Tick(5 * time.Second)
for {
select {
case <-futureTimer:
self.procFutureBlocks()
case <-self.quit:
return
}
}
}
// reportBlock logs a bad block error.
func reportBlock(block *types.Block, err error) {
if glog.V(logger.Error) {
glog.Errorf("Bad block #%v (%s)\n", block.Number(), block.Hash().Hex())
glog.Errorf(" %v", err)
}
}
// InsertHeaderChain attempts to insert the given header chain in to the local
// chain, possibly creating a reorg. If an error is returned, it will return the
// index number of the failing header as well an error describing what went wrong.
//
// The verify parameter can be used to fine tune whether nonce verification
// should be done or not. The reason behind the optional check is because some
// of the header retrieval mechanisms already need to verify nonces, as well as
// because nonces can be verified sparsely, not needing to check each.
func (self *BlockChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error) {
// Make sure only one thread manipulates the chain at once
self.chainmu.Lock()
defer self.chainmu.Unlock()
self.wg.Add(1)
defer self.wg.Done()
whFunc := func(header *types.Header) error {
self.mu.Lock()
defer self.mu.Unlock()
_, err := self.hc.WriteHeader(header)
return err
}
return self.hc.InsertHeaderChain(chain, checkFreq, whFunc)
}
// writeHeader writes a header into the local chain, given that its parent is
// already known. If the total difficulty of the newly inserted header becomes
// greater than the current known TD, the canonical chain is re-routed.
//
// Note: This method is not concurrent-safe with inserting blocks simultaneously
// into the chain, as side effects caused by reorganisations cannot be emulated
// without the real blocks. Hence, writing headers directly should only be done
// in two scenarios: pure-header mode of operation (light clients), or properly
// separated header/block phases (non-archive clients).
func (self *BlockChain) writeHeader(header *types.Header) error {
self.wg.Add(1)
defer self.wg.Done()
self.mu.Lock()
defer self.mu.Unlock()
_, err := self.hc.WriteHeader(header)
return err
}
// CurrentHeader retrieves the current head header of the canonical chain. The
// header is retrieved from the HeaderChain's internal cache.
func (self *BlockChain) CurrentHeader() *types.Header {
self.mu.RLock()
defer self.mu.RUnlock()
return self.hc.CurrentHeader()
}
// GetTd retrieves a block's total difficulty in the canonical chain from the
// database by hash and number, caching it if found.
func (self *BlockChain) GetTd(hash common.Hash, number uint64) *big.Int {
return self.hc.GetTd(hash, number)
}
// GetTdByHash retrieves a block's total difficulty in the canonical chain from the
// database by hash, caching it if found.
func (self *BlockChain) GetTdByHash(hash common.Hash) *big.Int {
return self.hc.GetTdByHash(hash)
}
// GetHeader retrieves a block header from the database by hash and number,
// caching it if found.
func (self *BlockChain) GetHeader(hash common.Hash, number uint64) *types.Header {
return self.hc.GetHeader(hash, number)
}
// GetHeaderByHash retrieves a block header from the database by hash, caching it if
// found.
func (self *BlockChain) GetHeaderByHash(hash common.Hash) *types.Header {
return self.hc.GetHeaderByHash(hash)
}
// HasHeader checks if a block header is present in the database or not, caching
// it if present.
func (bc *BlockChain) HasHeader(hash common.Hash) bool {
return bc.hc.HasHeader(hash)
}
// GetBlockHashesFromHash retrieves a number of block hashes starting at a given
// hash, fetching towards the genesis block.
func (self *BlockChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash {
return self.hc.GetBlockHashesFromHash(hash, max)
}
// GetHeaderByNumber retrieves a block header from the database by number,
// caching it (associated with its hash) if found.
func (self *BlockChain) GetHeaderByNumber(number uint64) *types.Header {
return self.hc.GetHeaderByNumber(number)
}
// Config retrieves the blockchain's chain configuration.
func (self *BlockChain) Config() *ChainConfig { return self.config }